Lawn mowing machine



9 G. E. THOMAS 2,451,589

LAWN 4 'MOWING MACHINE I Filed Nov. 26, 1945 zsheets-sneet 1 w WWM Oct. 19, 1948. 5 5, THOMAS 2,451,589

LAWN MOWING MACHINE Filed Nov. 26, 1 945 2 Sheets-Sheet 2 Patented Oct. 19, 1948 NITED STATES PATENT OFFICE Claims.

The present invention relates to a self-propelling mowing machine which does not require the constant attention of an operator and which, when properly adjusted and put into operation, can operate for prolonged intervals without supervision. A single operator will find it possible to supervise the operation of a plurality of mowing machines constructed in accordance with my invention and in this way there can be effected a great saving in manpower and in the cost of mowing lawns, golf courses, and the like.

My invention consists essentially of a Wheeled chassis which includes a vertically disposed pivot post having a radius arm arranged for rotation around the pivot post and a self-powered and self-propelling mower attached to the outer end of the radius arm. The radius arm steers the self-propelling mower in a generally circular path around the pivot post and there is a driving connection between the radius arm and certain of the wheels of the chassis which causes the wheeled chassis to advance while the mower is describing its generally circular path around the pivot post. Means are provided for steering the chassis in a desired path and when the steering means is properly adjusted the machine may be left unattended until it becomes necessary to discontinue the operation of the machine along its pre-set path.

The primary object of my invention is to provide a self-powered and self-propelling mowing machine which does not require the constant attention and supervision of an operator. Another object of the invention is to provide a chassis for a mowing machine which can be used with any power mower having caster wheels which permit the mower to travel about the pivot post of the chassis without side drag while the chassis advances.

detailed description which has reference to the accompanying drawings, wherein:

Figure 1 is a side elevation view of a mowing machine constructed in accordance with my invention;

Fig. 2 is a fragmentary rear elevation view of the mowing machine with portions thereof eliminated from the drawing for clarity of illustration;

Fig. 3 is a top plan view thereof;

' Fig. 4 is a sectional View taken in the direction of the arrows along the line 4-4 of Fig. 1;

Fig. 5 is a sectional view taken in the direction of the arrows along the line5--5 of Fig. 1;

Fig. 6 is a sectional view taken in the direction Further objects and advantages of the invention will be referred to in the following of the arrows along the line 6-6 of Fig. 1; and

Fig. 7 is a side elevation View of a self-powered and self-propelling mower suitable for use with my invention.

A self-powered and self-propelling mower is designated generally by the reference numeral 8. I have shown a mower having a frame 9, castertype wheels H], a drive or traction roller ll, and a cutting reel l2. The mower is illustrated as provided with an electric motor l3 which drives the cutting reel l2 and the traction roller ll through a series of belts and chains in a manner which will be apparent from an inspection of Figs. 1, 3 and 7. The caster wheels l0 should be sufiiciently spaced from the frame of the mower to permit the mower to follow the chassis while the chassis is being moved from place to place.

The outer end of a radius arm I4 is pivotally mounted on a pin I5 near the forward end of the frame 9 of the mower 8. The radius arm 14 is adjustable in length by virtue of the fact that its inner portion consists of spaced parallel members l6 and I! provided with upper and lower cross plates l8, while the outer end of the radius arm I4 consists of a single member H] which fits between the members [6 and H and the upper and lower plates 18 and is held in position by means of a pin 20 extending through the plates [8 and through apertures in the member 19.

The members [6 and I! of the radius arm i i are pivotally connected by means of a. pivot pin 21 to the lower flange 22 of a tubular member 23 which carries an upper flange 2 2 having a pulley 25 secured thereto by means of bolts 26. The tubular member 23 is positioned on a pivot post 27 having at its lower end an axle 28 on' which are mounted a pair of steering wheels 29. A collar 30 is fixed on the pivot post 2? and a wear plate 3! is interposed between this collar and the lower surface of the lower flange 22. A tubular member 33 surrounds the tubular member 23 and forms a part of the chassis of the machine which is described in greater detail hereinafter.

It should be noted at this point that the pin 2| permits the outer end of the radius arm M to rise or descend as the mower 8 travels over uneven terrain, and that the radius arm [4 steers the mower B in a generally circular path. The radius arm l4 causes the tubular member 2-3 and the pulley 25 to rotate for the purpose of driving the chassis in a manner more particularly described later in this specification.

The frame of the chassis includes side barsv 3 3 and .35 which diverge outwardly and rearwardly 'from the tubular member 33. The side bars 34 and 35 extend to and beyond upright side members 36 and 31, the extreme rearward ends of the side bars 3'3 and 35 forming handle members for manipulating the machine. A lower cross bar and an upper cross bar 39 extend between the members 36 and 3?. An aXle All is rotatabiy mounted at the lower ends of the upright members 36 and 3? and drive wheels M are fixed to the outer ends of the axle. A sprocket 52 is fixed against rotation near the mid portion of the axle 40 and is driven by a chain d3 which engages a sprocket 4 4 fixedly secured on a countershaft 25. The countershaft 45 is mounted in bearings 46 and t! which are secured respectively tothe upper ends of adjustable members 68 and 49. The adjustable members d3 andii are loosely secured to the cross bar 39 by means of bolts or pins 58. The lower ends of the members 58 and 49 are adjustable relative to the cross barfill by means of bolts 55 which extend through the cross bar 38 and throu h, the members 38. and 69 ina manner to permit the lower ends of the members ,Qtandfifi to be drawn nearer to the cross bar 33 for adjusting the tension in the drive;. b,elt, hereinafterdescribed.

The countershaft 45 also has fixed theretoa pulley 52 which is driven by a bolt 53 which also runs over the pulley 25. It will be apparent from the foregoing description that when the mowerB isguided through its circular path by the radius arm 14, the tubular member-23 and the pulley 25 vzillbe caused to rotate. Rotation of the pulley 25 causes rotation'of the pulley.52 through the belt 53. Rotation of the pulley, 52 causes rotation of the sprocketJM which rotates the sprocket .42 through the chain and drives .the axle it. and the drive wheels M to cause the chassis to advance. I The relative diameters of thepulleys 25 and 52 andthe sprockets 42 and Mare preferably such as to cause the chassis to advance during each complete revolution of the radius .arm [4 about the pivot post 21 through a distance which approximates the width .of the swath cut by the mowers. -When -the chassis is advancing in a straight line it will-be found that the mower 8 will cover the area twice, and I have found this to be advisable for the reason that it contributes to cleaner mowing and more favorable results.

The upright memberS'E extends above the side bart l and carries at its-upper enda yokefi i, in whichrests the notched lowerledge of a steering rodfifi. The forward end'of the steering rod 55 is pivotally secured .to asteering arm 55 by means of apin The opposite end of the steering arm 56 is secured against rotation on the upper end fidof the pivot post 21. Adjustment of the steering rod55 thus positions the wheelsZSl to cause the chassis to follow any desired path. The proper adjustment of the steering rod 55 is maintained by the notches in the loweredge .of the steeringrod which engage the yoke. 54.

- Electricpower may be supplied to the mowing machine by means of a cord which is connected to the female plugbdwhich is, secured to one leg of the yoke 54. The. power, is transmitted through conductors 5B and through a switchtl to brushes 62 and G3 which are mountedon brackets 56. and 65, respectively, attached to and insulated from the tubularmember 33. The lower flange 2?. on the tubular member 23 carries on its upper su.'-- .face an insulating disk 66 which is secured to the flange 22 by means of screws Bl. The insulating disk. 65 carries on its :upper surface a conducting ring 68 which is engaged by the brush 52 anda eecondconducting ringfiil; which, is engaged by the brush 63. Conductors if) and H are connected respectively to the conducting rings 58 and 59 and these conductors conduct the power to the electric motor [3. In the event that it is desired to substitute an internal combustion engine for the electric motor l3, the circuit just described may be used to control the ignition.

The mowing machine may be easily manipulated for making sharp turns while it is in operation merely by lifting on the handles formed by the rear ends of the side bars 3% and 35 to raise the drive wheels fill off the ground, whereupon the chassis may be turned about the front wheels 255. Themachine may also be moved over longer distances merely by pushing the chassis at a rate of speed. which enables it to keep pace with the mower B and which prevents that mower from revolving about the pivot post 27. On large lawns or golf courses, the machine may be set to advance in a straight line from one end of the area to be mowed to the other end thereof. It is possible when using a plurality of machines forpne operator to be located at each end of theareato bemowed so that the operators can successively turn the machines when they reach the end ofthe area. The steeringbar' 55 may be adjusted to cause the machine to follow an arcuatepath and this will be found desirable in many instances.

I have illustrated and specifically described what i now consider to be the preferred form of my invention. However, it is to be understood hat rnany variations and modificationsmay be resorted to without departing from :the broader aspects of the invention as defined by the following claims. 7 r 7' Having thus described my invention, I claim:

3.; In a machine of the character described'the combination of a vehicle having rear and front els, a rod extending upwardly fromthe axle of the front wheels, a steering lever connected to upper end of said rod and extending to the rear of the vehicle, a tube surrounding, said rod, a pulley secured to the upper end of said tube, a driving disk secured to the lower end of said tube, operating connections for rotating said tube and disk, a countershaft mounted on the rear of the vehicle, a second pulley secured to said counten shaft, a belt connecting said pulleys, operating connections between said countershaft and the axle of the rear wheels, a radius arm hingedly connected to said driving disk, a mower frame, a universal coupling connecting the outer end of said radius arm with said frame.

2. in a machine of the characterdescribed, the combination of a-vehicle having rear and front wheels, a rod extending upwardly. from the axle of the front wheels, a steering arm secured to the upper end of said rod, a steering lever connected with said steering arm and extendingnto the rear of the vehicle, a tube surrounding said rod, a pulley secured to the upper end of-said tube, a driving disk secured to the lower endof said tube, two ringssecured to the-upper side of said disk, a larger tube surrounding saidrfirst mentioned tube, rollers secured to the lower end of said larger tube and contacting saidrings .respectively, connections for rotating said first mentioned tube and disk, a countershaftmounted on the rear of the vehicle, a second pulley secured to said countershaft, a belt connecting said pulleys, a sprocket chain connection between said countershaft and the axle of the rear wheels, handle members secured to saidlargertube and extending to the rear of the vehicle, a radiusarm hingedIy, connected to said driving disk, a mower frame, a universal coupling connecting the outer end of said radius arm with the center of said frame, and caster Wheels on which said frame is supported.

3. A mowing machine comprising a chassis having wheels, a pivot post mounted on said chassis, a radius arm having one of its ends connected to said pivot post, a self-propelling mower attached to the other end of said radius arm and arranged to be steered by said radius arm in a generally circular path about said pivot post, and a driving connection between said radius arm and certain of the wheels of said chassis causing said chassis to advance during travel of said self-propelling mower around said pivot post.

4. A mowing machine comprising a self-propelling mower, a radius arm having one of its ends connected to said mower and having its opposite end connected to a pivot post to steer said self-propelling mower in a generally circular path about said pivot post, said pivot post being mounted on a chassis, wheels on said chassis, and a drivingoconnection between said radius arm and certain of said wheels causing said chassis to advance during travel of said self-propelling 25 mower around said pivot post.

5. A mowing machine comprising a chassis including a frame, rear drive wheels and front steer- REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 20 Number Name Date 901,605 Ferris 'Oct. 20, 1908 1,449,649 Brown Mar. 27, 1923 2,194,617 Scott Mar. 26, 1940 2,421,558 Goldsmith June 3, 1947 FOREIGN PATENTS Number Country Date 467,871 France Apr. 8, 1914 

